code: def paper_link(cls: str) -> Optional[str]:
      cls = importlib.import_module(
          "torch_geometric.datasets"
      ).__dict__[cls]
      doc = inspect.getdoc(cls)
      assert doc is not None
      match = re.search("<.+?>", doc, flags=re.DOTALL)
      return (
          None
          if match is None
          else match.group().replace("\n", " ")[1:-1]
      )
  
file_path: pytorch_geometric/torch_geometric/datasets/utils/cheatsheet.py
imports: import importlib
  import inspect
  import re
  from typing import Any, List, Optional
label_desc: Use image node_id 1 for calling a global function with example usage: paper_link(cls) and returns: unknown